No such things as "black holes"?

[GoSlash27]

http://www.universetoday.com/114802/there-are-no-such-things-as-black-holes/

That’s the conclusion reached by one researcher from the University of North Carolina: black holes can’t exist in our Universe  not mathematically, anyway...

Food for thought.

[WestAir]

To quote Jamie Hyneman from Mythbusters, "I'm dubious."

[Guest]

The fact is we can see things going on in the center of our galaxy that just don't make sense, like stars that are rotating around something really fast. Black holes are one theory to try and explain that. You can kind of think of a black hole as the same thing as dividing by zero. It's pretty much impossible to get your mind around it. I believe that it's pretty much a never ending rabbit hole. The more we learn about it, the more questions there are going to be.

Something else that may very well be related is the Double-slit experiment. When I was first introduced to this experiment in college, it blew my mind. How can something like this exist? It makes absolutely no sense to me how light can behave in such mysterious ways. I like the fact that there is so much we don't know. It would get real boring real fast if we knew everything.

[General Rarity]

*ahem*

https://briankoberlein.com/2014/09/25/yes-virginia-black-holes/

I'd like to say that the info you have is not so correct.

[Dominatus]

This amused me on iflscience. It's basically a load of bs. One paper that hasn't yet been subjected to peer review. One paper from someone who doesn't really understand the subject matter. Or something along those lines. If I'm incorrect I will eat my words.

[LaydeeDem]

Not mathematically? Math is all about things the shouldn't exist. What kind of mathematician is this guy?

[magnemoe]

Not mathematically? Math is all about things the shouldn't exist. What kind of mathematician is this guy?

Reacted too that myself, as other say galactic black holes fit well with observations, stellar ones are hard to spot anyway however we know of invisible objects larger than neutron stars.

Now add that its multiple ways star collapses mostly depending on size and if they have another star close.

More porbably he has found that some of the options don't give black holes.

[Alchemist]

The thing about the black holes is the very definition of event horizon. Relativity easily shows that there is point where orbital velocity equals escape velocity (for purely tangential movement!) equals the speed of light - anything just ballisticly flying closer (even a photon) will fall inside. But that is not the point of nothing can come out from! Even worse - what gravity potential is needed to stop a photon flying directly against it? Infinite.

[ibeinsane]

Having read the details of the papers I would say 3 things.

These papers are yet to be peer reviewed, You will amazed of the papers that get put onto arxiv.org and never become suitable for actual publication. (** I am not saying these papers are not suitable**)

These are for blackholes generated by the collapse of a star not for the formation of supermassive blackholes based at the centre of the galaxy. This paper does not address the formation of a supermassive blackhole.

The paper identifies a collapse in the coding as the outer shell of the star still accelerates towards the centre as the centre tries to explode. They state that the earlier part of the coding is sufficient to say the star will explode and not collapse but accept that they do not have the mathematics to fully compute the end of the star in their current model. (Does the outer section of the star continue to collapse into the centre or does it also explode?)

I would like to hazard a guess (based on general physics basis rather than mathematical modelling) where the outer shells could continue to accelerate inwards despite a core expansion to continue the formation of a black hole. This would of course be dependant on the size of the star which may require a star which is too large but should be confirmed or disputed when they model the shell overlap.

This paper describes the affect of hawkin radiation emitting mass from a forming blackhole faster than the increase in density at the centre of the star, causing a black hole to essentially evaporate faster than it's formation. Interestingly hawking radiation is only emitted by black holes but to my knowledge has not yet been officially observed. This paper uses the emission of a theoretical radiation from a black hole to prove that a black hole cannot form? That is like saying a chicken does not exist because of its egg.

[GoSlash27]

*ahem*

https://briankoberlein.com/2014/09/25/yes-virginia-black-holes/

I'd like to say that the info you have is not so correct.

Actually, the link that I posted agrees with yours. I made the (silly) assumption that people were going to actually *read* it before knee- jerking.

Best,

-Slashy

[Dominatus]

The evaporation description is basically correct. And ridiculous because the officially predicted amount of Hawking radiation a black hole emits is emitted at a very small constant rate; I think it may actually take longer than the current estimated life of our universe for a black hole to actually evaporate.

[YNM]

In my opinion : As the spacetime bends, time slows down. It'll take matter infinite amount of time to fall onto it. There're only near-black-holes than actual black holes - but as I read from an article, "the two are indistinguishable".

Does the author incorporates this, or does Hawking radiation already incorporates this (and makes my question doesn't exist) ? I think this might have a huge effect on cosmology, no ? Or maybe, stellar black holes goes from neutron stars, then "black holes" (ie. first it collapses into a neutron star, as more mass comes in, innermost mass become trapped inside event horizon) ?

[-Velocity-]

I'm studying for a Ph.D. in electrical engineering, so I'm familiar with academia. The reason I want to bring it up is because I've got first-hand experience- just because someone has a Ph.D. and works at some university doesn't mean that they know what they are talking about. Yes, usually it does, but I've seen plenty of examples where some Ph.D. professor is wrong about something- even some of their research.

Now, while a lot of people distrust science and education and revel in their own ignorance, and in particular will often point to examples of bad researchers (either in support of some crazy idea they have, or as proof that science cannot be trusted), the fact is that the scientific process is about forming a consensus. Everyone, even the smartest people in the world, are wrong about many of the things they think. That's why we form a consensus. That's why PEER REVIEW is CRITICAL. Whenever some person or group reports a result that contradicts the consensus and years of research and experimentation, no one believes them, and other scientists will try to disprove the contradictory findings. This kind of thing happens all the time in science, and findings that appear to fly in the face of scientific consensus and research are almost always shown to be some kind of experimental or analysis error. Sometimes, especially if the research was empirical in nature, identifying what caused this error can be highly valuable to other researchers in the field so that they do not fall victim to a similar problem.

In this particular case, the fact that this "proof" was not published in a peer-reviewed journal is very telling. It also flies in the face of overwhelming scientific consensus by some of the smartest minds on the planet and decades of observational evidence. In other words, this "proof" that black holes don't exist can be safely treated as bull!@#$.

Edited September 26, 2014 by |Velocity|

[vger]

This isn't the first time I've heard that black holes may be falling out of favor. For some odd reason though there was little splash when 'Hawking stopped believing in them.' But, you know how these news articles are. How many times have we been told now that "Earth 2" has been discovered... complete with a big confirmed population of bat people?

http://www.newrepublic.com/article/116442/stephen-hawking-thinks-black-holes-dont-exist

Edited September 26, 2014 by vger

[metaphor]

I find it kinda funny that 50-100 years ago people were ridiculed for suggesting that there were stars large enough that not even light could escape from them because it didn't make sense, and now it's the complete opposite (it doesn't make sense to not have black holes.

In my opinion : As the spacetime bends, time slows down. It'll take matter infinite amount of time to fall onto it. There're only near-black-holes than actual black holes - but as I read from an article, "the two are indistinguishable".

Does the author incorporates this, or does Hawking radiation already incorporates this (and makes my question doesn't exist) ? I think this might have a huge effect on cosmology, no ? Or maybe, stellar black holes goes from neutron stars, then "black holes" (ie. first it collapses into a neutron star, as more mass comes in, innermost mass become trapped inside event horizon) ?

Yes, from the point of view of an outside observer, it takes matter an infinite amount of time to fall into a black hole's event horizon. So from that point of view, black holes don't currently exist (but they would be observationally indistinguishable from "actual" black holes). Hawking radiation does take this into account, since this is a relativistic effect (time dilation). But this effect combined with quantum mechanics gives rise to things like the "firewall" theory. See this wiki page

[magnemoe]

This isn't the first time I've heard that black holes may be falling out of favor. For some odd reason though there was little splash when 'Hawking stopped believing in them.' But, you know how these news articles are. How many times have we been told now that "Earth 2" has been discovered... complete with a big confirmed population of bat people?

http://www.newrepublic.com/article/116442/stephen-hawking-thinks-black-holes-dont-exist

I don't like them, they are too introvert, the same way I don't like nuclear bombs as they are too noisy.

its important to have good reasons

[General Rarity]

Actually, the link that I posted agrees with yours. I made the (silly) assumption that people were going to actually *read* it before knee- jerking.

Best,

-Slashy

Sorry. It's just the quote that you posted seemed to be a 'TL;DR' of what the article was going to say... but it didn't. Simple misunderstanding.

[cantab]

We can be very confident that objects exist with enough mass and density to be inside their event horizon - we've observational evidence of them. As far as I'm concerned that's what a "black hole" is.

[YNM]

In my opinion : As the spacetime bends, time slows down. It'll take matter infinite amount of time to fall onto it. There're only near-black-holes than actual black holes - but as I read from an article, "the two are indistinguishable".

Does the author incorporates this, or does Hawking radiation already incorporates this (and makes my question doesn't exist) ? I think this might have a huge effect on cosmology, no ? Or maybe, stellar black holes goes from neutron stars, then "black holes" (ie. first it collapses into a neutron star, as more mass comes in, innermost mass become trapped inside event horizon) ?

Yes, from the point of view of an outside observer, it takes matter an infinite amount of time to fall into a black hole's event horizon. So from that point of view, black holes don't currently exist (but they would be observationally indistinguishable from "actual" black holes). Hawking radiation does take this into account, since this is a relativistic effect (time dilation). But this effect combined with quantum mechanics gives rise to things like the "firewall" theory. See this wiki page

I thought that, an observer falling into a black hole would still "see" that what falls in front of him takes an infinite amount of time ? And then, what falls behind him... I'm not sure here but I guess this could have an effect whether black holes could form or not : what someone sees and what someone doesn't.

Unless talking about time (and light) itself within a black hole becomes naive.

[Kruleworld]

I'm still trying to get past the stupid name of 'black hole', since it's obviously not a hole.

[rkman]

from the article:

"No singularity means no event horizon"

That's not true. A mass can be compact (dense) enough to form an event horizon, without it being a singularity.